Now that Fassbender has basically confirmed that yes this is connected to alien I think we can safely relax a little.

From slashfilm.com -

Fassbender (when asked if it is an alien movie and if it follows the continuity with the alien movies) -

“Oh, absolutely. There’s a definite connecting vein,. You realize you’re part of something else, but it’s definitely in keeping with the old ones.” … “When I read it, I was like, ‘Well, okay, another Alien. Where do you go with this idea?’ And then I sort of read the script, and it’s new, yet it’s in keeping with the old traditions as well. But there’s a whole new revelation within this film.” …. “The first ‘Alien’ [movies], they were thrillers. Something’s going on. It’s creeping, it’s sinister. Things are happening, it’s building, [and there are] different sorts of intrigues and politics going on between the different relationships on board. There’s action in it,” he said, “but the intelligence is what struck me when I read it. It’s more sort of like the original ones. There are things happening and building, and the intelligence of the first two-thirds of the film gets you ready for the action.”

Personally, I think this would be very interesting if it were a bit from column A and a bit from column B; you could have it as part of the Alien continuity without tying it too heavily to previous films. If you have Aliens in it, cool beans. If not, cool beans.

What I really want to see when I go to the cinema is a return to the style of sci-fi Alien best represents -- the mysterious and confronting.

I also really like the idea of Aliens being more amorphous than previously intended, and not necessarily due to host, but due to the fact they're f**kin' alien and make no sense via our narrow perceptions. Something like this is potentially fantastic because it opens the scope of the setting without limiting itself by being overtly imitative.